Amoxicillin in endo sealers reduces E. faecalis

Jul 15, 2010

Endodontic sealers mixed with amoxicillin inhibited the growth of Enterococcus faecalis significantly greater than sealers without amoxicillin, according to a study in the Journal of Endodontics (July 2010, Vol. 36:7, pp. 1170-1173).

E. faecalis has been frequently found in root-canal-treated teeth in prevalence values ranging from 30% to 90% of the cases (International Endodontic Journal, January 1998, Vol. 31:1, pp. 1-7). In addition, root-canal-treated teeth are about nine times more likely to harbor E. faecalis than cases of primary infections (Journal of Endodontics, May 2004, Vol. 30:5, pp. 315-320).

For this study, researchers from Marquette University School of Dentistry evaluated the antimicrobial effect of mixing amoxicillin with three different sealers when freshly mixed and set.

Using a direct contact test, Pulp Canal Sealer EWT (SybronEndo), AH Plus (Dentsply International), and RealSeal SE (Pentron Clinical Technologies) were freshly mixed with amoxicillin and placed on the side wall of the microtiter plate. A 10-µL bacterial suspension of E. faecalis was placed directly onto the fresh sealers, and sealers set one day, three days, and seven days after mixing.

The bacteria were allowed to dry in direct contact with the sealer sample. Fresh media was then added, and growth of the bacteria was measured by spectrophotometry over an eight-hour period.

The researchers found that all sealers mixed with amoxicillin showed complete inhibition of E. faecalis growth. Sealers mixed with amoxicillin had no statistical difference in inhibiting growth between freshly mixed samples and samples set for one day, three days, or seven days (p > 0.05). Sealers without amoxicillin did not inhibit E. faecalis growth, and the researchers found no statistical difference between freshly mixed and set samples (p > 0.05).

Sealers with amoxicillin were statistically different than sealers without amoxicillin when freshly mixed and set (p < 0.001).